1. Technical Field
The present invention relates to a head-mounted display device, which is a display device mounted on the head, and a control method for the head-mounted display device.
2. Related Art
There is known a head-mounted display device (a head mounted display, HMD), which is a display device mounted on the head. For example, the head-mounted display device generates image light representing an image using a liquid crystal display and a light source and guides the generated image light to the eyes of a user using a projection optical system and a light guide plate to thereby cause the user to recognize a virtual image.
In the head mounted display explained above, when the user operates a control unit of the head mounted display for the purpose of, for example, playback, stop, and fast forward of a video, it is likely that a virtual image displayed before the eyes of the user blocks the visual field of the user and hinders the operation. In order to solve such a problem, in the past, there is known a technique for picking up an image of a range including a display region with a camera, analyzing the picked-up image to detect the hands of the user, and reducing the visibility of an image displayed in a region formed between one hand and the other hand of the detected hands to improve the visibility of an external scene (e.g., JP-A-2010-211408).
With the head mounted display explained above, the user can enjoy images (videos) and music anywhere while wearing the head mounted display like, for example, eyeglasses. On the other hand, in a worn state of the head mounted display, since an image blocking an external scene is always displayed before the eyes of the user, the user could feel inconvenience. In order to solve such a problem, in the past, there is known a technique for detecting that a user is walking, automatically stopping image display of the head mounted display, and improving the visibility of an external scene (e.g., JP-A-09-211382).
Besides, JP-A-09-211382, JP-A-2008-116704, JP-A-2003-51993, JP-A-2007-134785, and JP-A-2004-96224 are examples of related art.
However, in the technique in the past for detecting the hands of a user, for example, it is likely that a malfunction due to misdetection occurs in a use in a public space. In the technique in the past for detecting that a user is walking, inconvenience for a walking user is reduced. However, in the past, there is a demand for also reducing, even when the user is not walking, inconvenience that the user feels, for example, when the user turns the user's face away from an image displayed on the head mounted display to shift the user's attention from the image.